WASHINGTON — With time growing short and warnings more dire, the first, fragile signs emerged Thursday of a possible compromise to raise the nation's debt limit and avert a potentially catastrophic default on Aug. 2.

Under a plan discussed by the Senate's top two leaders, President Barack Obama would receive enhanced authority to raise the debt limit at the same time procedures would be set in motion that could lead to federal spending cuts.

Word that Majority Leader Harry Reid, D-Nev., and Republican leader Mitch McConnell of Kentucky were at work on the fallback plan came as Obama and congressional leaders met for a fifth straight day in debt-crisis talks at the White House.

McConnell pronounced the session a good one and said, "We're going to continue to discuss a way forward over the next couple of days and see what happens."

A White House official said congressional leaders would consult with their rank-and-file members on the spending cuts and tax increases proposed by one side or the other so far, and negotiators would probably meet during the weekend.

Obama was slated to hold a presss conference Friday to address the status of negotiations at 11 a.m. ET.

The day's events were shadowed by warnings from Federal Reserve Chairman Ben Bernanke and JPMorgan Chase CEO Jaime Dimon. Speaking separately, the two men admonished bickering lawmakers that failure to avoid an unprecedented default could have a devastating effect on an already anemic U.S. economy.

Adding to the urgency, Moody's Investor Service has announced it is reviewing America's bond rating for a possible downgrade, and a Chinese rating agency, Dagong Global Credit Rating Co., also advised of a possible downgrade.

It was unclear when McConnell and Reid might unveil their legislation, or whether they would first present their ideas to Obama and others involved in the daily meetings at the White House.

McConnell said the plans had not been discussed at Thursday's White House session, which lasted less than 90 minutes.

One option under discussion by the Senate leaders is creation of a group of lawmakers who could recommend spending cuts, possibly including changes in benefit programs, that would be guaranteed a yes-or-no vote in Congress.

Another would be to couple any presidential request for a debt increase with spending cuts, including some that have emerged in private talks led first by Vice President Joe Biden, and now by Obama.

The seriousness of the situation was underscored throughout the day.

Testifying before a Senate panel, Bernanke said a default would deal a "self-inflicted wound" to the nation's economy, driving up interest rates and slowing recovery from the deep recession.

Dimon, speaking to reporters in New York, said default could prove catastrophic. "Why take that chance? I wouldn't take that chance," he said, answering his own rhetorical question.

Obama met with congressional leaders at the White House for a fifth straight day, although press secretary Jay Carney cautioned not to expect a "hallelujah moment" when it was over.

Talks have been stymied by a dispute over tax increases as part of any deal to cut future deficits. Obama and Democrats want them, while Republicans don't.

The concept under discussion by the Senate leaders is a more elaborate version of a plan McConnell suggested earlier in the week to a less-than-enthusiastic reception from conservatives.

In his first substantive remarks on McConnell's initial suggestion, Speaker John Boehner told reporters, "What may look like something less than optimal today, if we're unable to get an agreement might look pretty good a few weeks from now."

Carney said if there was no progress toward a bipartisan agreement on cuts by Friday, "then we have to begin looking at making sure that we fulfill our obligations to uphold the credit rating of the United States."

Treasury Secretary Timothy Geithner met privately at the Capitol with Senate Democrats, emerging to say: "We have no way to give Congress more time to solve this problem."

So the alarms covered a broad front: Geithner is a senior official in the Obama administration, Bernanke is the nation's central banker and Dimon the head of one of Wall Street's best-known firms.

Similar warnings have been directed at lawmakers repeatedly since Geithner announced that Aug. 2 was essentially the day of reckoning. The Treasury has been relying on unusual measures since early May to avoid breaching the current debt ceiling, which stands at $14.3 trillion.

Congress and the White House have responded to the warnings with a spate of high-profile meetings — but little if any apparent progress toward a solution.

In the cauldron of the White House Cabinet Room on Wednesday, Obama and top lawmakers bargained for nearly two hours Wednesday on spending cuts. According to House Majority Leader Eric Cantor, the president abruptly ended the tense meeting. "And he said to me, 'Eric, don't call my bluff,'" Cantor said. "He said, 'I'm going to the American people with this.'" After that, Cantor said Obama got up and declared, "I’ll see you tomorrow."

But a Democratic aide told NBC News, "Cantor's account of tonight's meeting is completely overblown ... Cantor rudely interrupted the president three times to advocate for short-term debt ceiling increases ... This is just more juvenile behavior from him and Boehner needs to rein him in."

Boehner on Thursday took steps during the day to present a common front with Cantor, his second-in-command, who has seemed at times to take a dominant role in the White House talks.

Reid criticized Cantor in unusually personal remarks on the Senate floor, saying he "has shown he shouldn't be at the table."

"And Republicans agree he shouldn't be at the table," he added, referring to published accounts of other GOP lawmakers criticizing Cantor anonymously.

Cantor brushed aside the criticism, and Boehner came to his defense at a news conference. "We have been in this fight together," he said, placing his arm around Cantor's shoulder, adding that any report that the Virginian has been "anything less than helpful is just wrong. ... We're in the foxhole."

Cantor and other members of the party leadership balked several days ago when Boehner privately shared details of a possible sweeping deal with Obama that could have meant higher taxes. The speaker announced he would no longer pursue the plan.

Apart from his role in the White House talks, Cantor staged a high-profile walkout from an earlier set of negotiations led by Biden, irritating some Democrats who noted the talks were near an end anyway.

Ironically, the cuts aired in those earlier conservations have moved center-stage in the White House talks, according to officials in both parties.

And Thursday's talks involving Obama were expected to focus in part on cuts in benefit programs, and in part on Democratic calls for higher government revenues — the very subject that triggered Cantor's earlier walkout.

Democrats have worked assiduously to exploit any differences between the two men. And for now, at least, the attention focused on Republicans has largely obscured the deep divisions among Democrats over the wisdom of reining in the cost of politically popular benefit programs such as Medicare and Social Security.

For their part, Republicans have advanced a stream of conservative proposals that have little chance of clearing a Democratic-controlled Senate.

At a news conference during the day, 10 Republicans took turns making the case for a balanced budget amendment to the Constitution, expected to come to a vote in the House next week.

Asked if the spending plan they had pushed through the House earlier this year would comply at any point in the next decade with their constitutional amendment, Boehner said, "I don't know, you'll have to ask" Rep. Paul Ryan, chairman of the Budget Committee and the plan's principal author.

The House-GOP-passed budget would generate deficits for more than a decade into the future, according to the Congressional Budget Office, and add about $9 trillion to the current debt in 10 years.

Copyright 2011 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

Video: Debt standoff

Closed captioning of: Debt standoff

>>>any further or more graphic evidence of how bad the economy is across this country right now, take a look at these pictures and we'll fill in the stories in just a moment. the human stampede that took place just for a shot at a home and a job. because things are so bad, because the stakes are so high, the talks that have been going on in washington to raise the nation's debt ceiling and then some could not be more important right now, and with a major deadline approaching,
august 2
, it's time to consider at least what happens if they don't have a deal. it's where we begin tonight, we'll start off our coverage with nbc's
kristen
welker at the
white house
.

>> reporter: tonight's discussion was not tense, that
president obama
continued to push for a very
big deal
, well that did not happen. and now here's the headline, there are no talks scheduled for tomorrow. the president and congressional leaders conceived for a fifth time in as many days, but still no deal to raise the debt limit. the treasury secretary has warned the nation will default on its loans if an agreement isn't reached by
august 2
.

>>we have looked at all available options and we have no way to give the congress more time to solve this problem.

>>what's required here in washington is that politicians understand now is not the time to play games, now is not the time to posture, now is the time to do what's right by the country.

>> reporter: this after tense talks on wednesday, the president reportedly said enough is enough to house majority leader
eric cantor
for his refusal to give in on tax hikes. cantor says mr. obama stormed out of the meeting which democratic sources deny.

>>there's really only one person who has not made any concessions and that is majority leader cantor.

>> reporter: today, cantor stood his ground.

>>we're not going to raise the debt ceiling if we don't have cuts in excess of that amount that we don't want to raise taxes.

>>let me just say we have been in this fight together. and any suggestion that the role that eric has played in this meeting has been anything less than helpful is just wrong.

>> reporter: the urgency to get a deal done heightened by two major credit agencies, warning they would downgrade the nation's top notch
credit rating
if a deal isn't reached soon. senate majority leader
harry reid
says it's a
wakeup call
.

>>we have a few hours, maybe few days to work this out.

>> reporter: there has been some chatter about moving the talks to
camp david
to create a relaxed and private environment to try to break this deadlock. that never gained any traction and my source tells me that the next time they will hold these talks will possibly, possibly be during the weekend.